Length-Weight Relationships of Fishes in Eight
Floodplain Lakes of Agusan Marsh, Philippines

Joycelyn C. Jumawan* and Romell A. Seronay

Biology Department, Caraga State University, Butuan City, Philippines

*corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Length-weight relationships (LWRs) of 16 fish species caught from eight floodplain lakes of Agusan Marsh in the Philippines in January 2014-2015 are reported. The species collected belong to nine families and were mostly introduced to the country. Samples were collected using five types of fishing gear. The “b” values in the LWR W= aLb ranged from 2.196 to 3.34 and showed a mean value of 2.95. These measurements of fishes from Agusan Marsh contribute baseline information for the management and conservation of this critical wetland. The dominance of introduced over the native species and the risks accompanying this scenario is discussed.

Marshes serve as a unique habitat for fishes due to its high production of vascular plant detritus, nutrients and it is spatially complex set-up. Tropical wetlands are hotspots of biodiversity (Gopal & Junk 2000). However, wetlands are subjected to increasing human pressure such as pollution, over utilization of natural resources and changes in natural flood regime which increases its vulnerability to invasion and dominance of introduced species (Junk 2002). The critical changes in management methods of this unique ecosystem have led to the declining fisheries diversity and production in most tropical countries (Dudgeon et al. 2006). . . . . read more

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